Oil leak in water heater burner..

My hot water tank's oil burner is leaking oil. It drips a bit when it runs only.. and I believe it's coming from the oil pump. The pump was replaced just over a year ago, and I had it services just in November.. so I think this is just a matter of something not being tightened enough during the last cleaning. Is this something I can attempt myself? I was going to just try and tighten this screw but wanted to check to make sure that wasn't making some sort of adjustment or something.